1. Field of the Invention
This invention relates to fishing tools and more particularly, to spear and overshot fishing tools designed to engage (in one aspect automatically) the receiving element or neck of a "fish" located in an oil or gas well in order to retrieve a drill string, tools or other objects from the well bore. The need to retrieve such objects is frequently realized in the drilling of oil and gas wells due to operating and mechanical failure and the need for a reliable, fluid-activated connecting and disengaging fishing tool for achieving this purpose is well recognized.
2. Description of Related Art
Incorporated here in its entirety by reference is the description of prior art in U.S. application Ser. No. 08/675,087 filed on Jul. 3, 1996 now U.S. Pat. No. 5,791,712.